The present invention relates to pouring spouts for glass or plastic bottles, and more particularly to a pouring spout of the type adapted for permanent fitment within the neck of bottle and which includes a combination of check valves and an air inlet conduit permitting liquid to be poured from within the bottle, but preventing liquid from being returned to the interior of the bottle.
A serious and continuing problem, particularly in the liquor trade, is the adulteration or replacement of expensive or rare liquor by a substitute of lower quality. Sales of the adulterated or substituted beverage can harm the reputation and cut into the total sales volume of the producer of the more expensive beverage and deprive the consumer of the quality of product for which he pays. While non-refillable pour spout devices have been designed previously to prevent this practice, the previously known non-refillable pour spouts have been less than satisfactory for various reasons.
For example, a non-refillable bottle cap and spout disclosed in Burnett U.S. Pat. No. 2,991,897 requires a specially-designed bottle neck for its attachment, and requires a bottle to be tipped always in a certain direction for pouring liquid from the bottle.
Musel U.S. Pat. No. 3,063,589 discloses a non-refillable pouring spout including a check valve which includes ample room for insertion of a tool to prevent the valve from closing, allowing the bottle to be refilled through the valve. Additionally, the location of the air inlet tube intended to permit flow of air into the interior of the bottle requires the bottle to be tipped in a particular direction in order to obtain the best pouring performance.
Kozlik U.S. Pat. No. 2,954,889 discloses another non-refillable bottle cap which requires that the bottle be tipped in a certain direction for pouring. Kozlik also discloses the use of a check valve in the air inlet tube of his bottle cap, but because of the construction of the Kozlik bottle cap it requires a specially designed bottle neck. Adoption of this bottle cap would therefore be undesirably expensive for liquor manufacturers.
Mills, et al., U.S. Pat. No. 4,217,988, discloses a non-refillable pouring spout which fits within the neck of a bottle and includes a check valve, but it would seem to be possible to refill a bottle through such a device by holding the bottle tipped to a horizontal attitude, partially submerged, or with the annular pouring opening partly covered. Benschoter U.S. Pat. No. 2,335,634 discloses a pouring valve which attempts to defeat refilling of a bottle by inclusion of a check valve and a vent tube directed toward the check valve.
One problem with some previously available non-refillable pour spouts is that they tend to pour unevenly as air flows into the bottle in which such spouts are used against the flow of liquid. In other previously known non-refillable spouts, a certain amount of liquid may drip or pour from the vent tube initially during pouring unless pouring is done in a particular direction.
What is needed, then, is an improved non-refillable pour spout which provides protection against refilling a bottle through either the liquid pouring duct or the air inlet tube. Such a spout should protect against refilling the bottle with the bottle in any attitude and also if the bottle is submerged. It is desirable that such a pour spout permit liquid to be poured from a bottle in which it is installed in any direction, with an even flow, and without liquid from within the bottle flowing outward through an air vent tube.